At new ideas at 17/10:
1. As mentioned as 15/10 before, every area has their own side "characteristic", so it should as same as the locker.
2. Keep continuous to the first point above. It should not only one type of the locker in whole building, metal drums / secrets room / drains etc, they should do the same trick.
3. Keep continuous to the second point above. Those special "hideout" also has their own side "characteristic" too.